LANDOVER, Md. — Chip Kelly’s madcap offense more than lived up to the hype.

Robert Griffin III’s comeback did not.

The two biggest storylines in the Eagles-Redskins season opener played out in opposite directions here Monday night, and the NFL might never be the same after Philadelphia’s 33-27 victory at FedEx Field.

The Eagles had to hold on for dear life, nearly blowing a 33-7 lead in the second half, but that didn’t make Kelly’s pro coaching debut any less memorable — or Griffin’s much-anticipated return less disappointing.

The fast-break offense Kelly brought from Oregon was an instant smash, leaving the Redskins gasping for air when they weren’t faking injuries as the Michael Vick-led Eagles sprinted — and we do mean sprinted — into halftime up, 26-7.

“It was a crazy game,” Vick said. “I’ve never been in anything like it. When the first quarter was over, I thought we were going into halftime.”

With the philosophy that 20 seconds between snaps is an eternity, Philly staggered the Redskins with a no-huddle attack that had running back LeSean McCoy running wild when Vick wasn’t standing in the pocket with his choice of open receivers.

That 1-2 punch produced some mind-boggling numbers at intermission, as McCoy rolled up 115 yards on 20 carries and Vick was 13-for-21 for 190 yards and two touchdowns. The Eagles ran 53 plays for 322 yards and 21 first downs in what Kelly called “a bizarre first half.”

To put those figures in perspective, McCoy’s rushing total at the break was enough to make him the NFL’s leading rusher for all of Week 1, and Philadelphia’s snap total in two quarters was three more than the 50 the Panthers ran the whole game Sunday in their loss to the Seahawks.

Robert Griffin III’s Redskins struggled against the Eagles.Patrick Smith/Getty Images

It could have been even uglier early on for Washington, too, if not for referee Ron Winter’s debatable ruling on the opening possession that a Vick pass was a fumbled lateral.

DeAngelo Hall returned the ball batted by teammate Ryan Kerrigan 75 yards for a touchdown. But that play didn’t faze the Eagles in the least, as they scored the next 33 points while spinning the Redskins and leaving their stunned crowd dizzy.

While Kelly and Vick were sending a jolt through the entire league, Griffin and the Redskins couldn’t have been slower out of the gate in the quarterback’s first game back after months of endless debate and speculation about his readiness following January knee surgery.

Running back Alfred Morris lost a fumble on Washington’s first play from scrimmage, the first of three turnovers in the Redskins’ first six snaps, and things didn’t improve until they finally found a rhythm down 26 points in the second half.

Redskins coach Mike Shanahan didn’t allow Griffin to play at all in the preseason as a precaution, and Shanahan’s franchise quarterback looked predictably rusty and tentative. Griffin finished with 329 yards and two touchdowns on 30-of-49 passing, but he threw two interceptions and was sacked three times.

Griffin and the Redskins were just too sluggish and mistake-prone early, which is when this matchup of NFC East rivals was decided.

“We had a case of the ‘can’t-get-rights’ early [first half],” a dejected Griffin said. “I can’t blame rust as an excuse. I’m responsible for how I play.”

McCoy and Vick cooled off considerably in the second half (McCoy finished with 184 yards and a touchdown on 31 carries while Vick ended 15-for-25 for 203 yards), but that might have been more human nature at work — up 33-7 — than being the Redskins figuring out Kelly’s scheme.

“With the personnel we have in this offense, we’re going to be hard to stop,” star left tackle Jason Peters said. “They’re going to have to defend us, or we’re going to run the score up — point blank. We’re not going to stop.”